"It appears what happened ... in some way Brexit and immigration was playing on his mind."

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Media captionDavid Yamba: Racist graffiti left me terrified

Mr Yamba welcomed the sentence, saying it reflected the seriousness of the offence but he did not think it was about Brexit, "just racism".

He said: "What's Brexit have to do with it? People can debate about it."

Mr Yamba said despite support from locals since the attack, he is considering leaving Greater Manchester.

Supt Marcus Noden, from Greater Manchester Police (GMP), described it as a "cowardly and spiteful act", adding there was "no place for this kind of hatred in Manchester or anywhere else".

He said: "No one should be subjected to this kind of abuse, especially in their own home."

The attack only came to light after Mr Yamba, who came to the UK from the Democratic Republic of Congo in 2006, tweeted a photo of his front door after he reported it, complaining police had not been to see him about it.

It led to Dowd's arrest and an apology from GMP Chief Constable Ian Hopkins.

Dowd was caught on CCTV and by police checking key-fob entries to the block.

He has now lost his tenancy at the housing association flats where he had lived for 25 years.